May 27, 2004

A weekly feature provided by scientists at the Hawaiian Volcano Observatory.

Pele was shopping around, but the home market was tough

Every day at the Hawaiian Volcano Observatory, we scan incoming data from field instruments Hawaiians had several stories about how their islands were formed. One version has Papa and Wakea mating and giving birth to the islands. The Big Island was first and Kaho'olawe was last. The more well-known story involves the goddess Pele and her travels to find a new home. Early geologists like that story because the order in which Pele visits the islands is the order in which they volcanically formed. Of course, fans of that story note that Pele visited islands that already existed, so she shouldn't really be credited with island formation. Is there a geologic interpretation to Pele's search for a home?

You betcha! But first we have to know the story. Folktale anthropologist Dr. Arlo Nimmo has researched as many versions of the Pele migration stories as are available in English. He found and read 48 versions and tried to summarize common bits.

Pele was born of divine parents, but the named parents varied in different versions. She lived in a far-off land, possibly Tahiti or Samoa and possibly mythical. Her family was large, consisting of a combined 44 sisters and half-sisters and 47 brothers. At least, that's Dr. Nimmo's count through the 48 versions. The true number is somewhat lower because many of the sibling names are epithets of one sibling.

As she grew to adulthood, her sibling rivalry with her sister Namakaokaha'i became a real conflict, ultimately forcing her to leave her homeland. At departure, she took a number of her other relatives and journeyed to Hawai'i.

Upon arrival in Hawai'i, she looked for a suitable home by digging a pit with her digging stick, Paoa. If successful, she could start volcanism as she used to do back home. If not, she would move on. She started on an atoll named Mokupapapa to the northwest and worked her way southeastward through the island chain. She finally settled at her current home in Kilauea.

So where's the geology? When she dug with Paoa and found a location unsuitable for her needs, it was usually because her volcanism was thwarted by the presence of water. According to Dr. Nimmo's tabulations, Pele visited over 100 sites on 12 different islands (including Nihoa, Kaula, and Lehua islands). Many of these named sites were active volcanically several hundred thousand years after the island-forming volcanism ceased. It's rejuvenated volcanism.

The evidence that these eruptions interacted with water is inside their deposits. Some deposits contain chunks of coral, within showing that the eruptions blasted right through reef. Most of these locations are at low elevations (think of where Diamond Head and Punchbowl are) and likely were accompanied by strong explosions as encountered groundwater flashed into steam.

Did Hawaiians witness these eruptions? Almost certainly not. The most recent of these eruptions occurred a few tens of thousands of years ago, and Hawaiians first saw the products probably at most two thousand years ago. They could have deduced the nature of the eruptions by close observation and probably did. And they recorded these observations in Pele's failures and also in her continued conflict with her sister, Namakaokaha'i. Pele's testy sister considers the ocean her domain and continues to fight with Pele when aware of her presence.

Pele's real estate search takes an interesting turn when she gets to Haleakala. Here, she finally finds a crater to her liking and stays a while. She ultimately finds the crater too large to keep warm and moves on to the Big Island. Her stay at Haleakala is the first time she is not driven out by water, and Haleakala is the first volcano as one goes to the southeast down the chain that has not yet experienced these rejuvenated volcanic eruptions. Interesting coincidence or shrewd native deduction?

This epic story has much more than these geologic tidbits and deserves a read in any one of many available versions. Action, love, fighting, geology, superpowers, and complete, complex characters are the necessary components for any successful movie and are all here awaiting your perusal.

Activity update

Eruptive activity at Pu`u `O`o continues. The Banana flow, which breaks out of the Mother's Day lava tube a short distance above Pulama pali, made it to the coastal flat on May 2 and to the Wilipe`a lava delta on May 26. As of May 27, lava is near, but not at, the coastline. Lava viewing has been good most of the week. The national park has marked a trail to within a short distance of the flow. There is no eruptive activity in Pu`u `O`o's crater except for sporadic minor spattering.

No earthquakes were reported felt on the island for the week ending May 27.

Mauna Loa is not erupting. The summit region continues to inflate slowly. Seismic activity remains low, with only 2 earthquakes located in the summit area during the past week.